Good on you for having such a nice guy machinist, and for finding the problem.
After several heartaches, I now have all engines I build (for the first
time, when I'm unfamiliar with the engines history) -
Block is hot-tanked, decked (after a dry build to measure piston to deck
clearance), bored and honed, line-bored, crank (even brand new ones) gets
cracktested, measured for all bearings in terms of size, roundness, taper,
ground if required, rod big ends resized, new cam bearings installed. Then,
another dry build to measure all critical clearances. Only then do I
actually build the engine. So I actually build the engine about three times
before I get it assembled.
You can use a simple vernier caliper to check a ton of stuff on the engine
to reasonable accuracy. A $35 caliper is accurate to .001", which is fine
for seeing what size the journals are, for example. So while I've got a half
dozen Micrometers, they stay in the chest until needed while the Vernier
gets used every day.
Why am I contributing this to the list? Because I hated building a nice
Cooper S race engine that lasted 45 minutes, only to be told after the fact
"well, I always get the rods resized - didn't you?" Like, why didn't you
tell me that LAST WEEK! Cost me set of rods, and a new crank, and
ultimately a new straight cut gearset for the tranny, and that came to well
over $2,000!
Cheers, Brian
At 04:40 PM 1/20/98 -0500, you wrote:
>Paul, No I didn't check these things. I am sure you are right about
>short-life motors but
>
>a) I can use plastiguage OK, but don't have access to accurate enough
>dial guages or large enough mics. for checking the mains journals or for a
>bent crank.
>
>b) If I pay an engineer to grind the crank and supply the matching bearing
>shells, then I should be able to rely on him to do just that.
>
>Actually he now has the block, crank and bearings back and is checking it
>out. I have dealt with him before, he is very good and he always does a
>good job. He has offered to set up the crank for me (not apart of the
>original deal) FOC. He rang thisafternoon to say that the problem is with
>a damaged front bearing cap which is "out of round". He is trying to get
>hold of another and then will line bore it to get it right.
>
>Engine wasn't running when I got (given) the car, and I don't know anything
>about history or PO.
>
>Thanks also to Les, Daryl, Dave, Jim and others !
>
>I'll let you know the outcome.
>
>Guy
>
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